I have read for some time that I am not alone in experiencing the negative performance hit excel has taken due the higher encryption which has been added. This is easily observed when using macros to unprotect and protect several sheets. This is very frustrating as it has added up to 20 seconds of wait time at initial startup. Prior to Excel 2016 this was achieved seemingly instantaneous. I have also read that Microsoft will not do anything to fix this due to not wanting to lower security features in any way. I am hoping this is not the case. In fact there are ways to alleviate this problem without sacrificing security. First, why is it neccesary to unprotect or protect several pages initially at startup? This is necessary because the "UserInterfaceOnly" is not a saved element. This is an optional argument of the protect method. If the UserInterfaceOnly element was either saved upon closing the workbook, or this option was separated from the protect method, there would be no performance hit because of this. 20 seconds saved for each time the program is opened. Another and even better solution in my view is to allow multiple sheets to be set as a group - much like shapes and graphical elements. In this way you could protect or unprotect multiple sheets and only take the performance hit one instead of for every sheet. In addition UserInterfaceOnly does not work with imports such as querytables. The sheet must be Unprotected which means you take a performance hit each time. These are big issues that Microsoft needs to address.
